表面活性剂对渣油胶体性质影响的初步研究

PRELIMINARY STUDY ON THE EFFECTS OF SURFACTANT ON THE COLLOIDAL PROPERTIES OF RESIDUE

以轮古常压渣油(LGAR)为原料,分别加入不同质量分数的表面活性剂十二烷基磺酸钠(SDS)、十六烷基-三甲基溴化铵(CTAB)和油酸(Oleic acid),考察了它们对LGAR的80℃运动黏度、体系胶体稳定性、四组分含量及数均相对分子质量的影响。实验结果表明,随着加入的SDS质量分数的增加,LGAR的80℃运动黏度先减小后增大,在0.7%时达到最小值,体系胶体稳定性增强,沥青质含量和数均相对分子质量的变化与80℃运动黏度变化规律一致;随着加入的油酸质量分数的增加,LGAR 80℃运动黏度持续下降,体系胶体稳定性增强,芳香分含量增加,沥青质含量和数均相对分子质量持续下降;随着加入的CTAB质量分数的增加,LGAR的80℃运动黏度增加,体系胶体稳定性减弱,组分分布有所变化,但无明显变化规律。因此,SDS和油酸对渣油有较好的降黏作用,是较好的沥青质稳定剂;而CTAB不能降低LGAR黏度,对渣油胶体体系无明显的稳定作用。

The different mass concentrations of the three surfactants, sodium dodecyl sulfonate （SDS）, cetyltrimethyl ammonium bromide （CTAB） and oleic acid were added into Lungu atmospheric residue （LGAR）, respectively, to investigate their effects on the 80℃ kinematic viscosity, colloidal stability, contents and average relative molecular mass of SARA four fractions of LGAR. It is shown that in LGAR, with the increase of SDS mass concentration, the 80℃kinematic viscosity of LGAR decreased first, then increased, the least value of which was at 0.7% of SDS. The colloidal stability of LGAR was enhanced, and the changes of contents and average relative molecular mass of asphaltene in LGAR showed the same discipline as the 80℃ kinematic viscosity of LGAR. With the increase of oleic acid mass concentration in LGAR, the 80℃ kinematic viscosity of LGAR reduced, the colloidal stability of colloidal system was enhanced, the content of aromatic fraction increased and the content and average relative molecular mass of asphaltene decreased, while the addition of CTAB could increase the 80℃ kinematic viscosity of LGAR and made the colloidal stability of LGAR worse. It is proved that SDS and oleic possessed the properties of viscosity reduction for AR and were the good asphaltene stabilizers, while CTAB was no obviously effect on the stability of residue colloidal system.